Health

Patterns of maternal weight gain in pregnancy

Article Abstract:

Although maternal weight gain is perceived to be an important clinical measure used to monitor the nutritional status of the mother, few studies have been performed to determine normal patterns of weight gain during pregnancy. A retrospective study of 1,145 pregnant women (mean age of 27 years) was performed to identify normal patterns of maternal weight gain, to determine factors that influence weight gain, and to define the relationship between weight gain and infant birth weight. The mean maternal weight at booking (initial office visit) was 140 pounds, the mean total weight gain was 24 pounds, and the average weekly weight gain was 0.8 pounds. The highest rates of weight gain were observed during weeks 16 to 24 and weeks 32 to 36 of gestation, and the lowest rates were observed before week 16 and after week 36. The greatest weight gain (25 pounds) occurred in women who had booking weights between 130 and 150 pounds, and the lowest weight gain (22 pounds) occurred in women weighing over 150 pounds at booking. Mean weight gain was less in women under 20 years of age than in those over 25, and less in smokers than in nonsmokers; mean weight gain was greater in women with high blood pressure than in those with normal blood pressure, and in those with a body mass index in the third quartile than in the first or fourth quartiles. Women who had heavier babies experienced a greater mean weight gain, but there was no difference in the mean weight gain of women who gave birth to infants who were small for their gestational age than in those who gave birth to infants who were normal in size. There was no relationship between maternal weight gain and gender of the infant or social class of the mother. The factors that were associated with maternal weight gain were high blood pressure, previous births, smoking status, and body mass index. (Consumer Summary produced by Reliance Medical Information, Inc.)

Women who gain more fat during pregnancy may not have bigger babies: implications for recommended weight gain during pregnancy

Article Abstract:

In the late 1960s, two studies showing a weak relationship between maternal weight gain and infant birthweight were published. The studies reported that women who gain only a small amount of weight during pregnancy have a greater chance of having a low birthweight baby. Prior to 1970, women in the US were advised to limit their weight gain during pregnancy to 22 pounds, whereas women in the UK were told to limit their weight gain to 28 pounds. At the same time, it was reported that the average birthweight was lower for babies born to women in the US than those born to women in the UK. As a result, the National Academy of Sciences recommended that the desirable maternal weight gain should be increased to 24 pounds. In many cases, this has been interpreted to mean that women should gain at least 24 pounds during pregnancy. However, the results of two recent surveys in indicate that the average maternal weight gain in the US is close to 33 pounds. This implies that excessive weight gain is being encouraged, even though it has not been proven that excessive weight gain during pregnancy results in a bigger baby. To investigate this issue, the relationship between birthweight and maternal weight gain was determined in 115 Scottish housewives. The women who gained more weight during pregnancy did not give birth to heavier babies. These findings indicate that excessive weight gain during pregnancy results in an increase in maternal weight, but not necessarily in increased birthweight. (Consumer Summary produced by Reliance Medical Information, Inc.)